Cell reselection and cell handover are basic operations of a terminal in a mobile communications network, and are foundations on which the terminal ensures a network connection and service continuity in a movement process.
In an existing cell reselection process, the terminal performs measurement for only a neighboring cell broadcast by a serving cell. Only the neighboring cell of the serving cell can be used as a target cell for the cell reselection when a signal of the serving cell becomes weak. The terminal is dropped from a network when a signal of the neighboring cell of the serving cell is weaker or the neighboring cell of the serving cell has no signal. In a cell handover process, the terminal performs measurement for only a neighboring cell indicated by the serving cell. Only the neighboring cell indicated by the serving cell can be used as a target cell for the cell handover when the signal of the serving cell becomes weak. A service of the terminal is interrupted when a signal of the neighboring cell indicated by the serving cell is weaker or the neighboring cell indicated by the serving cell has no signal. In an actual scenario, a case in which there is an isolated cell is encountered. For example, besides a French window of a high-rise building, there is usually signal coverage of another cell far from the isolated cell, and the signal coverage is relatively strong, but signal coverage of the isolated cell is relatively weak. Because the other cell is relatively far from the isolated cell, and the isolated cell and the other cell are not mutually configured as neighboring cells, a terminal is dropped from a network or a service of the terminal is interrupted according to the cell reselection and handover processes in other approaches.
Therefore, when a serving cell has no neighboring cell or a neighboring cell cannot satisfy a condition of cell reselection or cell handover, a solution in the other approaches causes a terminal to be dropped from a network or a service of the terminal to be interrupted.